Excel 2003 and earlier versions can run across a bug when you choose to filter the information. The message in the status bar becomes stuck on "Filter Mode," instead of displaying how many records were filtered. According to Microsoft, this should only occur when you have over 51 formulas in your list, you have filtered the list, each cell contains a cell reference and Excel changes the status bar before the filter process is complete. While Microsoft never fixed the bug, it has released a work-around.
Select the column or columns, by clicking the letters at the top of the spreadsheet, that you have filtered. Click the "Data" menu at the top of the window, move your mouse over "Filter," and select "AutoFilter." This will remove the filter from your data.
Click the "Tools" menu, then select "Options" from the drop-down menu. Select the "Calculation" tab at the top of the Options window.
Click the box next to "Manual," and click "OK" to close the window. Excel will no longer perform calculations automatically.
Select your data, and click the "Tools" menu. Move your mouse over "Filter," and select "AutoFilter." Click the arrow at the top of the column that you want to you for filtering your data. Select your desired option, and the data will be filtered, but the message in the status box will tell you how many records you have filtered, instead of being stuck saying "Filter Mode."
When you are done filtering your data, you can turn calculation back on by going to the Calculation tab again and selecting "Automatic."